This invention is directed to the stationery field and in particular card files which hold the card but allow it to be flipped and read on both sides.
There is a particular need for a card file that is portable and may be used by students to organize research materials and notes that may be collected on standard index cards. It would be particularly useful to have a card file which would be capable of insertion in a standard loose-leaf ring notebook. U.S. Pat. No. 3,292,632 to Hopen discloses a card file that might at first glance appear to fill this need. The Hopen invention has a basic deficiency. As with most card files, there is an attempt to prevent the cards from dropping out of the file. Hopen suggests that the problem is solved by notching or preshaping the index cards. This costly and very inconvenient method essentially eliminates the utility of such an invention. Pre-notching is not practical to the supplier or the user for general usage. Card file systems as described in U.S. Pat. No. 2,530,604 to Emblen and U.S. Pat. 2,318,489 to Iuculano have similar deficiencies. There are many additional card filing systems utilizing cards having notches, slits, slots, pockets or tabs to hold the cards in position and prevent the inadvertent misplacement. U.S. Pat. No. 697,592 to Zevy discloses leafs with tabs which fit into slots and are glued in place to hold the leaf in place.
In these disclosures the cards have specially formed notches, tabs or whatever. The card width when referred to the depth of the notches, slots, slits or whatever is less than the length of the slot into which the card is to be inserted. By leaving an extension longer than the slot, the card is held in place and prevented from being inadvertently removed.
It is an object of this invention to provide a card file which holds the cards in place, and prevents cards from inadvertent removal.
It is an additional object of this invention to provide a card file wherein the cards may be flipped over to uncover the card below and to observe or write on both sides of the cards.
It is a primary object of this invention to provide a card file that holds the cards in place, which utilizes standard index cards that may be purchased in any stationery store and used in the invention with no modification.
It is an additional object of this invention to provide a card file which stores the index cards on a substantially rigid sheet which may be further stored in a binder, such as a standard ring binder.
It is an additional object of this invention to provide a card file which may be incorporated, as part of another item such as of a spiral notebook or ring binder.
It is an additional object of this invention to provide a card file which permits standard index cards to be inserted, stored, viewed from either side, removed, rearranged or replaced at the will or desire of the user.
It is an additional object of this invention to provide a convenient, inexpensive, and yet durable card file which may be utilized by students and others using essentially all standard materials available in stationery stores.
These and other objects have been attained in the present invention which accomplishes the needs described above.